Michael Strahan may have a legion of fans around the world – but his biggest supporter has always been his mom.And to mark Mother's Day on Sunday, the Good Morning America star took to Instagram to share a lovely picture of himself and his mother Louise.READ: Robin Roberts shares bittersweet message as she asks fans for supportThe father-of-four shared a happy picture of the pair of them on the set of Good Morning America, as they sat at a table in front of an adoring crowd. VIDEO: GMA's Michael